An optical system, in particular for microlithography, includes a beam splitter, which has at least one light entry surface. The beam splitter is arranged in the optical system so that the angles of incidence with respect to the surface normal which occur at the light entry surface during operation of the optical system lie in the range of 45°±5°. The beam splitter is produced in the [110] crystal cut.

A method of making a polarizer can include applying a liquid with solid inorganic nanoparticles dispersed throughout a continuous phase, then forming this into a different phase including a solid, interconnecting network of the inorganic nanoparticles. This method can improve manufacturability and reducing manufacturing cost. This method can be used to provide an antireflective coating, to provide a protective coating on polarization structures, to provide thin films for optical properties, or to form the polarization structures themselves.

The invention relates to a device and a method for characterizing a microlithographic mask. A device according to the invention has an illumination optical unit for illuminating structures of a mask intended for use in a lithography process in a microlithographic projection exposure apparatus, a detector unit, and an evaluation unit for evaluating the data recorded by the detector unit, wherein the detector unit is configured for the spatially resolved determination of both the intensity and the polarization state of the respectively impinging light emanating from the mask.

The invention relates to a sensor comprising: a radiation source to emit radiation having a coherence length towards a sensor target; and a polarizing beam splitter to split radiation diffracted by the sensor target into radiation with a first polarization state and radiation with a second polarization state, wherein the first polarization state is orthogonal to the second polarization state, and wherein the sensor is configured such that after passing the polarizing beam splitter radiation with the first polarization state has an optical path difference relative to radiation with the second polarization state that is larger than the coherence length.

The invention relates to a sensor (SE) comprising: a radiation source (LS) to emit radiation (LI) having a coherence length towards a sensor target (GR); and a polarizing beam splitter (PBS) to split radiation diffracted by the sensor target into radiation with a first polarization state and radiation with a second polarization state, wherein the first polarization state is orthogonal to the second polarization state, and wherein the sensor is configured such that after passing the polarizing beam splitter radiation with the first polarization state has an optical path difference relative to radiation with the second polarization state that is larger than the coherence length.

An assembly for collimating broadband radiation, the assembly including: a convex refractive singlet lens having a first spherical surface for coupling the broadband radiation into the lens and a second spherical surface for coupling the broadband radiation out of the lens, wherein the first and second spherical surfaces have a common center; and a mount for holding the convex refractive singlet lens at a plurality of contact points having a centroid coinciding with the common center.

The invention relates to a device and a method for characterizing a microlithographic mask. A device according to the invention has an illumination optical unit for illuminating structures of a mask intended for use in a lithography process in a microlithographic projection exposure apparatus, a detector unit, and an evaluation unit for evaluating the data recorded by the detector unit, wherein the detector unit is configured for the spatially resolved determination of both the intensity and the polarization state of the respectively impinging light emanating from the mask.

A polarization filter includes a multilayer structure including a first plurality of elements and a second plurality of elements alternating between each other. The first plurality of elements and the second plurality of elements have different thicknesses, and the multilayer structure is configured to interact with unpolarized light incident on the multilayer structure and separate transverse electric (TE) waves and transverse magnetic (TM) waves of the unpolarized light.

An optical pulse for an extreme ultraviolet (EUV) light source may be formed by illuminating a semiconductor material of a modulation system with a first light beam having a first wavelength; applying a voltage to the semiconductor material for a time duration, the applied voltage being sufficient to modify an index of refraction of the semiconductor material such that a polarization state of a light beam having a second wavelength passing through the semiconductor material is modified to pass through at least one polarization-based optical element of the modulation system; and forming an optical pulse by passing a second light beam having the second wavelength through the semiconductor material during the time duration.

An optical system for a microlithographic projection exposure apparatus for operation in the EUV includes a polarization-influencing arrangement having first and one second double reflection surface units, each having first and second reflection surfaces, in each case arranged directly adjacent at a distance d1 and at an angle of 010 relative to one another. The first reflection surface of the first double reflection surface unit and the second reflection surface of the second double reflection surface unit are arranged directly adjacent at a distance d2 and at an angle of 010 relative to one another, with d2>5*d1. Light incident on the first reflection surfaces forms an angle of 4310 with the first reflection surfaces. Light incident on the first reflection surface of the first double reflection surface unit is reflected toward the second reflection surface of the second double reflection surface unit.